Graves is a good lane bully, but doesn't scale particularly well into late game.
Ashe is the utility ADC, with permaslow passive, global vision ability, and global stun which can be used as engage at close range.
As Graves you'll need a support who can lock enemy down (which isn't difficult to come about: Thresh, Leona, Morgana, and Blitzcrank are some of the most popular support picks) so you can get kills. If you can't get kills early as a lane bully, you're losing lane. If you like playing aggressively, Graves is really good. Also see Lucian, who is played pretty much like Graves.
As Ashe, if you just farm well and avoid dying/be even with your lane opponent, you'll still be good enough for teamfight purposes. Her DPS is a little lacking, but she provides a lot of utility. If the team doesn't have hard engage or not a lot of peel, Ashe could help fill that role.